The Rev. Bob Billings, former executive director of the Moral Majority and a force in the spread of private Christian schools emphasizing "basic" curriculums, is under consideration for the top federal post dealing with private and parochial schools.

"He has been told that the job looks very promising," Billings' wife Charlotte said last night when asked about a report by columnists Rowland Evans and Robert Novak that her husband would be named assistant secretary of education for nonpublic education.

However, she cautioned that Billings, who left today on a trip to Taiwan, has not heard definitely that the job is his. And a White House official said that he had no knowledge that Billings had been selected for the position although his name has been mentioned in connection with several posts. p

It was learned last night that one possibility under study is to name Billings to a newly created post of special assistant to the secretary of education for nonpublic schools and to do away with the assistant secretary position.

As former executive director of Moral Majority, Billings worked closely with Moral Majority's leader Jerry Falwell and lobbied for Christian causes in Washington for years.

In the 1970s, Billings gained notoriety in New Right political circles when he led the campaign against efforts of the Internal Revenue Service to limit the tax-exempt status of church schools.

New Right fund raiser Richard A. Viguerie writes in his best-selling book, The New Right: We're Ready to Lead, that Billings "organized a campaign that caused about 200,000 letters to be received by the IRS protesting their plans. At least another 200,000 letters and cards of protest were received by Jimmy Carter in the White House and members of Congress."

Billings also was one of the first religious leaders to attend the Religious Roundtable, a New Right organization that has sought to activate thousands of conservatives on behalf of New Right positions on school prayer, abortion, sex education and national defense.

Billings graduated from Bob Jones University in Greenville, S.C., and later founded Hyles-Anderson College in Hammond, Ind., and some 400 private schools and colleges, Charlotte Billings said yesterday. Billings was en route to Taiwan and could not be reached.

Charlotte Billings said that the private schools and colleges started by her husband were aimed at providing better academic training for young people than is available in public schools, with a special emphasis on "the Three R's."

President Reagan has pledged that he will support federal education policies that promote greater "choice" in the range of schools available to parents. He supports tuition tax credits for parents sending children to private schools.

Although tax credits are supported by Catholics, some heads of fundamentalist schools are opposed to them on grounds that any kind of federal aid would result in federal interference in their operations